GASTEROMYCETES. 



[ 286 



GELIDIUM. 



burst, but set free their spores by decaying. 

 Lastly, the Podaxinei bear much resemblance 

 to the Trichogastres, but they always contain 

 a central fleshy column, called the hymeno- 

 phore. The young plants exhibit a peridium 

 passing internally into a fleshy mass hollowed 

 into labyrinthiform cavities (fig. 279), with a 

 solid column in the centre of all. The cavi- 

 ties are lined by a membrane bearing basi- 

 diospores (fig. 281). The gleba sometimes 



Fig. 278. 



Fig. 279. 



Fig. 280. 



Fig. 281, 



Secotium erythrocephalum. 



Fig. 278. Natural size. 



Fig. 279. Vertical section. 



Fig. 280. Vertical section through the head, showing 

 the labyrinthiform cavities. 



Fig. 281. Portion of a septum dividing the loculi, bear- 

 ing basidia. Magnified 400 diameters. 



breaks up into a pulverulent mass of spores 

 and filaments ; sometimes it is permanent. 

 The internal structure of this order presents 

 many points of great morphological interest, 

 but rather as regards the mode of arrange- 

 ment and composition of the tissues than 

 the character of the ultimate elements them- 

 selves, which consist of the ordinary filamen- 

 tous interwoven tissue of Fungi in the general 

 mass of the structure, and of globular loosely 

 packed cells in the sporiferous regions. 



Synopsis of the Families. 



1. PODAXINEI. Peridium dehiscent, en- 

 closing a sinuously excavated, fleshy, spori- 

 ferous mass, falling to powder or permanent 

 when mature, with a central solid column. 



2. HYPOG^I. Peridium indehiscent, 

 coating a fleshy, sporiferous mass. Subter- 

 raneous, at first distended with jelly. 



3. PHALLOIDEI. Peridium dehiscent, 

 enclosing a fleshy, sporiferous mass, which 

 emerges from the burst peridium as a club- 

 shaped or capitate column, or a globular 

 network of wrinkled fleshy processes, coated 

 on the sporiferous surfaces with a dark- 

 coloured foul-smelling slime (composed of 

 minute spores imbedded in mucus). 



4. TRICHOGASTRES. Peridium double, 

 more or less distinct, dehiscent, enclosing a 

 multilocular, fleshy, sporiferous mass, which 

 finally breaks up into dust, without a central 

 column. 



5. MYXOGASTRES. Peridium at first 

 developed from a mucilaginous matrix, sac- 

 like, dehiscent, emitting a reticulated fila- 

 mentous structure bearing the spores. (Mi- 

 nute, almost microscopic Fungi.) 



6. NIDULARIACEI. Peridium dehiscent 

 and then forming a cup or nest, containing 

 either one or many globose oval or discoid 

 conceptacles, lined with filaments bearing 

 spores. 



BIBL. See the Families. 



GASTROCHJ3TA, Duj. A genus of In- 

 fusoria, of the family Enchelia (Duj.). 



Char. Body oval, with one side convex, 

 the other being traversed by a longitudinal 

 furrow, which is furnished with vibratile 

 cilia principally at the ends. 



G.fissa (PI. 24. fig. 7). Body semitrans 

 parent, colourless, oval, truncated in front, 

 with a very minute, blunt point at the 

 middle of the posterior margin, convex and 

 smooth above. Aquatic; length 1-400". 



BIBL. Dujardin, Infus. p. 385. 



GELATINE. This chemical proximate 

 principle constitutes the basis of the various 

 forms of white fibrous tissue, as existing in 

 the true skin, areolar tissue, tendon, ligaments, 

 the swimming-bladder of fishes (isinglass),&c. 



It possesses no microscopic characters; 

 it forms a most valuable vehicle for the co- 

 louring matters of liquids for injection. 



BIBL. See CHEMISTRY. 



GELIDIUM, Lamx. A genus of Cry- 

 ptonemiacese (Florideous Algae), of which one 

 species (G. corneum) is very common on our 

 shores. It has a red, pinnated, horny frond, 

 from two to six or eight inches high ; very 



